Blend4Web not detected by Blender 2.8.3
Sadly, per this discussion thread at the Blend4Web website, it would appear that the latest version of Blender that supports Blend4Web would be 2.79, so the answer to your question would be &quot;Not yet supported, unless you install and use Blender 2.79 for that specific purpose.&quot;
On the bright side, there's nothing at all preventing you from using older versions of Blender on the same system as a newer version of Blender, and the Blend4Web folks kindly host a download of Blender 2.79 on their downloads page for your convenience, and I do believe that you can still find older versions of Blender on the official Blender website if you look around a bit.